Copyright © University of Cambridge. All rights reserved.

'Jam' printed from http://nrich.maths.org/

Show menu


This is a game for two players. You need the game board shown below. It is easy to draw if you want to play this on paper. You will need two different colour pencils (highlighters are good to use).

The dots are towns. The 9 straight lines are roads going to and through the towns.

Each player takes a turn to colour over a whole straight road (even though it may pass through several towns).
The first player to colour three roads going to or through the same town wins.

This text is usually replaced by the Flash movie.

Click on a line to colour it.

Does it matter which player goes first?
Which road is it best to colour first?

What happens to the game if you add another road or two?

Can you analyse the elements and structure in the following games and the correspondences between them?  Describe the patterns that show they are equivalent games that can be played using equivalent strategies.

We suggest tackling them in the order given.